dingy Posted April 28, 2011 #1 Posted April 28, 2011 (edited) I have a set of Denso COP coils in hand. They came out of a 2007 Honda CBR 1000. This unit would replace the larger coils used on the bike now. 129700-4840 10484 printed on coil end - 08H31 stamped in same area The Ignitech TCI module maker said it would handle the coils lower primary resistance. Going to give these a try on the bike as I am not really happy with where I had to install rear pair of coils. A little other discussion on this at link below. Started a new thread to maybe get some fresh inputs. http://www.venturerider.org/forum/showthread.php?t=58797 All 4 coils primary's measure 1.4 ohms All four coils secondary's measure 13.46K ohms. How do I tell which of the 2 input terminals is the common 12V+ terminal. I can see no markings which indicate internal wiring. My meter is not sensitive enough to differentiate between 13.46K ohms only and 13.46k ohms plus the 1.4 ohms coils in series. Could I just test wire up a circuit. Put plug in & grounded. Put 12v + to one side of coil & 12v - to other side of coil (this attached to plug ground). Open negative side at coil. This seems like it should fire plug. If it does polarity guessed at correct. If not flip polarity at coil pins. It should fire if it didn't before. Schematic shows two wiring choices. Anyone see any fault with this. Picture of COP coil on head is just a random one I came across for an idea what they look like installed. Gary Edited April 28, 2011 by dingy
Freebird Posted April 28, 2011 #2 Posted April 28, 2011 I may be wrong but I actually think that they will fire either way.
dingy Posted April 28, 2011 Author #3 Posted April 28, 2011 (edited) In the schematic, the version on the right (titled Choice 'B') is the way the 1st gen schematics show the coil wiring. Just guessing it won't work the other way. Just don't want to destroy coil testing !! Gary Edited April 28, 2011 by dingy reworked captions in schematic
Freebird Posted April 28, 2011 #4 Posted April 28, 2011 Well, I would not think that you would hurt a thing in the world if you had the polarity wrong. The only other way I see to tell would be to look at the wiring diagram of the bike that they came off of. It is obvious that the wiring harness would only plug in one way. If you could see the wiring harness you might be able to tell which pin is positive and which is negative. Also, are the pins the same size? It seems that the positive and negative pins on some coils are a different width to distinguish them. I'm even thinking that the pins on my RSV coils are different widths but I don't remember for sure and am not home to look.
Freebird Posted April 28, 2011 #5 Posted April 28, 2011 Here is a discussion that I found on another site. It seems that on the Honda, there is a black wire with a white stripe that is the negative. It seems from the pictures that would mean the the right pin is probably the negative or common. http://www.superhawkforum.com/forums/knowledge-base-40/coil-cap-mod-23004/
MiCarl Posted April 28, 2011 #6 Posted April 28, 2011 (edited) I'm with Freebird - if the primary has two connectors it won't care about polarity. Your "WORKS" diagram looks suspect to me. The back side of the secondary should be directly grounded to provide a return path for the high voltage. This diagram shows it grounding through the (+) which would cause spikes on the electrical system which I can't imagine the electronics would like. Since the coil fires when the TCI interrupts the ground (-) on the primary I'd think the "DOESN'T WORK" hook up would ruin the TCI. You didn't come up with those ohming out a defective coil did you? **EDIT** Just looked at the pictures for the first time. I didn't realize you were talking about a coil over plug set up. The secondary on that guy is going to ground back through the primary wiring. If that guy is wired wrong I can see where it might damage the ignition module (not the coil). If the module works with the stock 1st gen coils and wiring then it is switching the ground side. I'd think you'd want your "WORKS" diagram configuration to keep the high voltage away from the module. Looking at the link Freebird provided it appears to me that the CBR is likely a computerized HEI where the module sends a high voltage pulse on the (+) lead to fire the coil. The primary and secondary both go to chassis ground on the black/white (-) lead. If I'm right and the Ignitech unit functions like a stock TCI I bet it won't fire the coils at all. You might want to check and with Ignitech and see if that module is compatible with the CBR (not just the coil primary resistance). Edited April 28, 2011 by MiCarl
mbrood Posted April 28, 2011 #7 Posted April 28, 2011 If the drawing is "literal" you can see by the "tab" that the left side (as viewed from the "tab") is common to +12V. http://www.bergall.org/temp/venture/cbr1000.jpg http://cbr.deathace.net/gfx/2008_uk_wd.jpg
dingy Posted April 28, 2011 Author #8 Posted April 28, 2011 This is a picture of the wiring harness that was listed at same time as coils. I have tried to contact seller to see if there is a higher resolution copy of this picture available. Coil plugs are the four gray ones in the center of picture I am guessing. http://i1007.photobucket.com/albums/af193/gdingy101/wiringharnesscbr1000.jpg Thanks for schematic Mike, tried to find one last night with no success. I am on pain killers for bulging disc in back and concentrating is a might tough. Carl questioned if I had ohm checked a bad coil. I have checked all four coils and they all read identical. In the schematic I drew of coil wiring choices, I redid headers, I don't know which way will work. Made them Choice 'A' & Choice 'B' Gary
MiCarl Posted April 28, 2011 #9 Posted April 28, 2011 From the schematic mbrood posted I see that I was incorrect about the CBR being a (+) pulsed HEI. Gary, I thought your diagram was for Venture coils. If it's the CBR coils I believe it. I think you're going to want to wire them like "choice B" for the earlier reason I stated - you don't want the ignition module or the coil primary to see the voltage spike from the secondary. Of course you'll sort that out when you find out how the connector is wired.
bkuhr Posted April 29, 2011 #10 Posted April 29, 2011 Gary, just googled 'ignition coil schematic' every one that came up with neg pulse trigger showns both primary and secondary coils common ground simular to your choice 'A' Would suggest getting a CBR schematic just to be sure
Ozlander Posted April 29, 2011 #11 Posted April 29, 2011 The go fast boys are more concerned about the direction of the electrons thru the plug. The center electrode being hotter emits electrons easier, so they want it to be negative in respect to the side electrode. And that depends on how the coil is wired inside. They test it and wire it to make that happen. In the real world, it doesn't make a tinkers dam which way you wire it. That being said, choice A is how an ignition coil is normally drawn in a ignition circuit. That and a buck might get you a cup of coffee.
dingy Posted April 29, 2011 Author #12 Posted April 29, 2011 Was able to come up with a way to identify internal wiring. We have an Xray machine at work that we use to assist in part failure diagnosis. In picture , to the left are the two terminals, the top terminal has the fine & heavy wire attached to it. Bottom terminal only has the fine wire. Fine wire would be the 13.46K ohm secondary & heavy wire is the 1.4 ohm primary. Gary
Hulign Posted April 29, 2011 #13 Posted April 29, 2011 Oh man If I had a toy like that at work I would probably glow in the dark! Way too much fun for me to be trusted with. A few of the Vmax guys were doing this, I thought about it for a while but since it dynoed at 134hp I thought I should leave well enough alone. Sure wish my Venture had that power. Lucky that I can go borrow my old Vmax anytime I want You bike looks like a crazy ongoing project...the best kind in my opinion Good luck Frank
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